An elevation is different. It shows the face of something, or perhaps more correct, the projection of an object/s to a plane. But my testing suggests it produces SECTIONS, not elevations.
Yes, you can use abbreviations in tables and figures. All abbreviations used in tables and figures should be defined in the table note or figure caption, respectively, even though the abbreviations will be also be defined in the text if they are used there.
Abbreviations are shortened forms for written words or phrase used in a place of the whole (e.g., vol for volume). Acronyms are words formed from the initial letter of each of the successive parts or major parts of a compound term (e.g., CBC for complete blood count).